Image Converter MCP Server

Instructions

Implementation Reference

• src/index.ts:173-189 (registration)

  Registration of the 'get_image_info' tool in the ListTools handler, including its name, description, and input schema.

  {
    name: 'get_image_info',
    description: '获取图片文件信息',
    inputSchema: {
      type: 'object',
      properties: {
        image_path: {
          type: 'string',
          description: '图片文件路径（与image_data二选一）'
        },
        image_data: {
          type: 'string',
          description: '图片数据（Buffer或base64字符串，与image_path二选一）'
        }
      }
    }
  },

• src/index.ts:264-276 (handler)

  MCP handler for 'get_image_info' tool in the CallToolRequestHandler switch statement. It calls converter.getImageInfo and formats the response text.

  case 'get_image_info': {
    const { image_path, image_data } = args as { image_path?: string; image_data?: string };
    const info = await this.converter.getImageInfo(image_path, image_data);
    const source = image_path ? `文件路径：${image_path}` : '上传文件';
    return {
      content: [
        {
          type: 'text',
          text: `图片信息：\n${source}\n格式：${info.format}\n尺寸：${info.width}x${info.height}\n文件大小：${info.size} bytes\n颜色通道：${info.channels}\n颜色空间：${info.space || '未知'}`
        }
      ]
    };
  }

• src/converter.ts:48-55 (schema)

  ImageInfo interface defining the structure of image information returned by getImageInfo.

  export interface ImageInfo {
    format: string;
    width: number;
    height: number;
    channels: number;
    size: number;
    space?: string;
  }

• src/converter.ts:295-330 (helper)

  Core implementation of getImageInfo in ImageConverter class using Sharp to extract metadata from image file or buffer.

  async getImageInfo(imagePath?: string, imageData?: Buffer | string): Promise<ImageInfo> {
    try {
      let buffer: Buffer;
      let size: number;
  
      if (imageData) {
        if (typeof imageData === 'string') {
          const base64Data = imageData.includes(',') ? imageData.split(',')[1] : imageData;
          buffer = Buffer.from(base64Data, 'base64');
        } else {
          buffer = imageData;
        }
        size = buffer.length;
      } else if (imagePath) {
        await fs.access(imagePath);
        const stats = await fs.stat(imagePath);
        buffer = await fs.readFile(imagePath);
        size = stats.size;
      } else {
        throw new Error('必须提供imagePath或imageData参数');
      }
  
      const metadata = await sharp(buffer).metadata();
  
      return {
        format: metadata.format || 'unknown',
        width: metadata.width || 0,
        height: metadata.height || 0,
        channels: metadata.channels || 0,
        size: size,
        space: metadata.space
      };
    } catch (error) {
      throw new Error(`无法获取图片信息: ${error instanceof Error ? error.message : String(error)}`);
    }
  }